Kaleidoscope

How it works

You’ve seen small kaleidoscopes, but now it’s time to put yourself in the picture! Step into this three-way mirror and watch how you stretch into infinity in all directions.

Things to try or ask around the exhibition

How many reflections of yourself can you count in the distance?

Does your image get reversed along the line or reflections or does it stay the same?

Is your most distant reflection as bright as your closest reflection?

Background

The three mirrors form an equilateral triangle. This triangle’s sides are all the same length and its corners all form the same sized angle (60 degrees). Light reflects off you and onto each mirror’s surface. It then reflects off the surface, and bounces into the other mirrors, creating multiple reflections of you!

Your image becomes darker as it gets further away because light has been reflected off the mirrors multiple times. Each time the light strikes a mirror, some of the light energy is absorbed. The mirror actually becomes a tiny bit warmer as it absorbs the energy of the light! What would happen if the angle between the mirrors decreased? The numbers of images would increase! This is because the decreasing angle allows light to bounce between the mirrors more times.

When the two mirrors are at at 0 degree angle to each other, the number of images is theoretically infinite because light bounces back and forth between the mirrors without escape. But because the mirrors are absorbing a little bit of the light energy each time light hits them, your images keep getting darker so that they are not truly infinite.

Finding the science in your world

When you're in a public bathroom, or a changing room that contain mirrors both in front and behind you, you can see a similar effect of a 'never ending' line of reflections of yourself.

Kaleidoscope toys also use mirrors joined together as an equilateral triangle, but at the end of the kaleidoscope tube, a container full of beads or crystals creates symmetrical patterns, due to reflections within the mirrors.